Hybrid vehicle

ABSTRACT

When a starting point water temperature Twst is equal to or lower than a threshold value Twref 1 , catalyst warm-up control is executed, and when a cooling water temperature Tw becomes higher than the threshold value Twref 1  or an operation time top of an engine becomes equal to or higher than a threshold value topref 1 , the control of the engine is shifted from the catalyst warm-up control to normal control. When the starting point water temperature Twst is higher than the threshold value Twref 1  and is equal to or lower than a threshold value Twref 2 , PN suppression control is executed, and when the cooling water temperature Tw of the engine becomes higher than the threshold value Twref 2  or the operation time top of the engine becomes equal to or higher than a threshold value topref 2 , the control of the engine is shifted from the PN suppression control to the normal control.

INCORPORATION BY REFERENCE

The disclosure of Japanese Patent Application No. 2015-177563 filed onSep. 9, 2015 including the specification, drawings and abstract isincorporated herein by reference in its entirety.

BACKGROUND

1. Technical Field

The disclosure relates to a hybrid vehicle, and particularly, to ahybrid vehicle including an engine, a motor, and a battery.

2. Description of the Related Art

In the related art, as an internal combustion engine system, there issuggested an internal combustion engine system which includes aninternal combustion engine, and a particulate matter (PM) removingdevice provided in an exhaust passage of the internal combustion engine,and in which, when the cooling water temperature of the internalcombustion engine is lower than a reference temperature and the numberof PM particles in exhaust gas after passing through the PM removingdevice is more than a reference particle number, an operation point(engine rotational speed and engine load) of the internal combustionengine is changed so that the PM particle number in the exhaust gas fromthe internal combustion engine decreases (for example, refer to JapanesePatent Application Publication No. 2012-219746 (JP 2012-219746 A). Inthis system, a PM particle number in exhaust gas discharged out of thesystem is reduced by the above-described control.

Among hybrid vehicles which include an internal combustion engine and anelectric motor for vehicle driving and a battery that exchanges powerwith this electric motor and which drive the engine while the engine isintermittently operated, there is a hybrid vehicle that executes thefollowing first control or second control according to a cooling watertemperature (starting point water temperature) at the time of the startof operation of the internal combustion engine. In the first control,when the starting point water temperature is equal to or lower than afirst predetermined temperature, the output of the internal combustionengine is limited to a first predetermined output or lower, and acatalyst of an exhaust gas control apparatus of the internal combustionengine is warmed up until the cooling water temperature becomes higherthan the first predetermined temperature. In the second control, whenthe starting point water temperature is higher than the firstpredetermined temperature and is equal to or lower than the secondpredetermined temperature, the output of the internal combustion engineis limited to a second predetermined output or lower that is greaterthan the first predetermined output and an increase in the PM particlenumber is suppressed until the cooling water temperature becomes higherthan the second predetermined temperature. In this case, at theexecution of the first control and the second control, when a rise inthe cooling water temperature is relatively gentle, the execution timesof the first control and the second control may become relatively long.If the execution times of the first control and the second controlbecome relatively long, the time during which the output from the motorand eventually the discharge power from the battery are apt to berelatively great may continue for a relatively long time, and the powerstorage proportion of the battery may drop relatively greatly. For thisreason, it is preferable to prevent the execution times of the firstcontrol and the second control from becoming relatively long.

SUMMARY

An object of the hybrid vehicle of the disclosure is to prevent timeduring which output from an engine is limited from becoming relativelylong.

The hybrid vehicle of the first aspect of the disclosure is outlined byproviding a hybrid vehicle including an engine and a motor for vehicledriving; a battery that exchanges power with the motor; a controllerconfigured to control the engine and the motor so as to be drivendepending on a required output for vehicle driving while the enginebeing intermittently operated, the controller, (i) executes normalcontrol in which the engine is controlled so that a target output of theengine according to the required output is output from the engine when astarting point water temperature that is a cooling water temperature atthe start of the operation of the engine is higher than a secondpredetermined temperature higher than a first predetermined temperature,(ii) executes first control in which the engine is controlled so that anoutput of the engine is limited to a first predetermined output or lowerand a catalyst of an exhaust gas control apparatus of the engine iswarmed up when the starting point water temperature is equal to or lowerthan the first predetermined temperature, then shifts to the normalcontrol when the cooling water temperature becomes higher than the firstpredetermined temperature or when a first predetermined time has lapsedfrom the start of the operation of the engine, (iii) executes secondcontrol in which the engine is controlled so that the output of theengine is limited to a second predetermined output or lower that isgreater than the first predetermined output and a discharge amount ofparticulate matter from the engine is suppressed when the starting pointwater temperature is higher than the first predetermined temperature andis equal to or lower than the second predetermined temperature, andthen, shifts to the normal control when the cooling water temperaturebecomes higher than the second predetermined temperature or when asecond predetermined time has lapsed from the start of the operation ofthe engine.

In the hybrid vehicle according to the first aspect, the engine and themotor are controlled so as to be driven depending on the required outputfor vehicle driving while the engine being intermittently operated.Then, the normal control is executed in which the engine is controlledso that the target output of the engine according to the required outputis output from the engine when the starting point water temperature thatis the cooling water temperature at the start of the operation of theengine is higher than the second predetermined temperature higher thanthe first predetermined temperature. Additionally, the first control isexecuted in which the engine is controlled so that the output of theengine is limited to the first predetermined output or lower and thecatalyst of the exhaust gas control apparatus of the engine is warmed upwhen the starting point water temperature is equal to or lower than thefirst predetermined temperature, and then the shift to the normalcontrol is performed when the cooling water temperature becomes higherthan the first predetermined temperature or when the first predeterminedtime has lapsed from the start of the operation of the engine. Moreover,the second control is performed in which the engine is controlled sothat the output of the engine is limited to the second predeterminedoutput or lower that is greater than the first predetermined output andthe discharge amount of particulate matter from the engine is suppressedwhen the starting point water temperature is higher than the firstpredetermined temperature and is equal to or lower than the secondpredetermined temperature, and then, a shift to the normal control isperformed when the cooling water temperature becomes higher than thesecond predetermined temperature or when the second predetermined timehas lapsed from the start of the operation of the engine. Therefore,since the shift to the normal control is performed when the coolingwater temperature becomes higher than the first predeterminedtemperature or when the first predetermined time has lapsed from thestart of the operation of the engine, during the execution of the firstcontrol, the execution time of the first control can be prevented frombecoming relatively longer when a rise in the cooling water temperatureis relatively gentle, as compared to the shift to the normal controlperformed only when the cooling water temperature becomes higher thanthe first predetermined temperature. Additionally, since the shift tothe normal control is performed when the cooling water temperaturebecomes higher than the second predetermined temperature or when thesecond predetermined time has lapsed from the start of the operation ofthe engine, during the execution of the second control, the executiontime of the second control can be prevented from becoming relativelylonger when a rise in the cooling water temperature is relativelygentle, as compared to the shift to the normal control performed onlywhen the cooling water temperature becomes higher than the secondpredetermined temperature. As a result, the time during which the outputfrom the motor and eventually the discharge power from the battery areapt to become relatively great can be prevented from continuing for arelatively long time, and the power storage proportion of the batterycan be prevented from declining relatively greatly.

In such a hybrid vehicle of the first aspect of the disclosure, thesecond predetermined output may be set so that the second predeterminedoutput when the starting point water temperature is low becomes smallerthan that when the starting point water temperature is high. When thestarting point water temperature is low, it is believed that, ascompared to that when the starting point water temperature is high, thetemperature within the cylinder of the engine is low and the dischargeamount of particulate matter from the engine is apt to increase. Thedischarge amount of particulate matter from the engine can be moreappropriately suppressed by setting the second predetermined output sothat the output of the engine when the starting point water temperatureis low becomes smaller than that when the starting point watertemperature is high.

Additionally, in such a hybrid vehicle of the first aspect of thedisclosure, the second predetermined time may be set so that the secondpredetermined time when the starting point water temperature is lowbecomes longer than that when the starting point water temperature ishigh. As described above, when the starting point water temperature islow, it is believed that, as compared to that when the starting pointwater temperature is high, the temperature within the cylinder of theengine is low and the discharge amount of particulate matter from theengine is apt to increase. Therefore, the execution time (time forsuppressing particulate matter from the engine) of the second controlcan be made more suitable by setting the second predetermined time sothat the second predetermined time when the starting point watertemperature is low becomes longer than that when the starting pointwater temperature is high.

In the hybrid vehicle of the first aspect of the disclosure, when thestarting point water temperature is higher than the first predeterminedtemperature and is equal to or lower than the second predeterminedtemperature, the controller may shift to the normal control after thesecond control is executed when a stop time from the end of a previousoperation of the engine to the start of a current operation of theengine is equal to or greater than a third predetermined time, and mayexecute the normal control without executing the second control when thestop time is smaller than the third predetermined time. When the stoptime is relatively short, it is believed that the temperature within thecylinder of the engine is still relatively high and the discharge amountof particulate matter from the engine does not increase so much. Thedischarge amount of particulate matter from the engine can be suppressedby shifting to the normal control after the second control is executedwhen the stop time is equal to or greater than the third predeterminedtime. When the stop time is smaller than the third predetermined time,the output from the motor and eventually the discharge power from thebattery can be further prevented from becoming relatively great byexecuting the normal control without executing the second control.

In such a hybrid vehicle of the first aspect of the disclosure, thethird predetermined time may be set so that the third predetermined timewhen the starting point water temperature is low becomes shorter thanthat when the starting point water temperature is high. When thestarting point water temperature is low, it is believed that, ascompared to that when the starting point water temperature is high, thetemperature within the cylinder of the engine is apt to be low. Whetheror not the second control is executed can be more appropriatelydetermined by setting the third predetermined time so that the thirdpredetermined time when the starting point water temperature is lowbecomes shorter than that when the starting point water temperature ishigh.

In the hybrid vehicle of the disclosure, the controller may shift to thenormal control when an integrated air quantity from the start of theoperation of the engine reaches a predetermined air quantity or greatereven when the cooling water temperature does not become higher than thesecond predetermined temperature and the second predetermined time hasnot lapsed from the start of the operation of the engine, during theexecution of the second control. If this is the case, the execution timeof the second control can be further prevented from becoming long.

In such a hybrid vehicle of the first aspect of the disclosure, thepredetermined air quantity may be set so that the predetermined airquantity when the starting point water temperature is low becomesgreater than that when the starting point water temperature is high. Asdescribed above, when the starting point water temperature is low, it isbelieved that, as compared to that when the starting point watertemperature is high, the temperature within the cylinder of the engineis low and the discharge amount of particulate matter from the engine isapt to increase. Therefore, the execution time (time for suppressingparticulate matter from the engine) of the second control can be mademore suitable by setting the predetermined air quantity so that thepredetermined air quantity when the starting point water temperature islow becomes greater than that when the starting point water temperatureis high.

BRIEF DESCRIPTION OF THE DRAWINGS

Features, advantages, and technical and industrial significance ofexemplary embodiments of the disclosure will be described below withreference to the accompanying drawings, in which like numerals denotelike elements, and wherein:

FIG. 1 is a configuration view illustrating the outline of theconfiguration of a hybrid vehicle 20 as an example of the disclosure;

FIG. 2 is a configuration view illustrating the outline of theconfiguration of the engine 22;

FIG. 3 is a flowchart illustrating an example of a control routine to beexecuted by an HVECU 70 of the example;

FIG. 4 is an explanatory view illustrating an example of a map in whicha relationship between starting point water temperature Twst and upperlimit power Pe2 is determined;

FIG. 5 is an explanatory view illustrating an example of a map in whicha relationship between the starting point water temperature Twst andthreshold value topref2 is determined;

FIG. 6 is a flowchart illustrating an example of a control routine of amodification example;

FIG. 7 is an explanatory view illustrating an example of an aspect ofthe state of the engine 22 and the presence/absence of execution of PNsuppression control, in the case of the modification example;

FIG. 8 is an explanatory view illustrating an example of a map in whicha relationship between the starting point water temperature Twst andthreshold value toffref is determined;

FIG. 9 is a flowchart illustrating an example of a control routine of amodification example;

FIG. 10 is an explanatory view illustrating an example of a map in whicha relationship between the starting point water temperature Twst andthreshold value Garef is determined;

FIG. 11 is an explanatory view illustrating an example of an aspect whenthe PN suppression control in the case of the modification example isexecuted;

FIG. 12 is a configuration view illustrating the outline of theconfiguration of a hybrid vehicle 120 of a modification example; and

FIG. 13 is a configuration view illustrating the outline of theconfiguration of a hybrid vehicle 220 of a modification example.

DETAILED DESCRIPTION OF EMBODIMENTS

Next, modes for carrying out the disclosure will be described usingexamples.

FIG. 1 is a configuration view illustrating the outline of theconfiguration of a hybrid vehicle 20 as an example of the disclosure.The hybrid vehicle 20 of the example, as illustrated in the drawing,includes an engine 22, a planetary gear 30, motors MG1, MG2, inverters41, 42, a battery 50, and an electronic control unit 70 for a hybridvehicle (hereinafter referred to as an HVECU).

The engine 22 is constituted as an internal combustion engine thatoutputs power by using gasoline, gas oil, or the like as fuel. FIG. 2 isa configuration view illustrating the outline of the configuration ofthe engine 22. The engine 22, as illustrated in FIG. 2, inhales airpurified by an air cleaner 122 via a throttle valve 124, and injectsfuel from a fuel injection valve 126 to mix air with fuel. Then, byinhaling this air-fuel mixture into a combustion chamber 129 via anintake valve 128 and exploding and combusting the air-fuel mixture withelectrical spark caused by an ignition plug 130, a reciprocal motion ofa piston 132 depressed by the energy of the explosion and combustion isconverted into a rotational motion of a crankshaft 26. Exhaust gas fromthe combustion chamber 129 is discharged to external air via apurification apparatus 134 having a purification catalyst (ternarycatalyst) 134 a that purifies detrimental constituents of carbonmonoxide (CO), hydrocarbon (HC), and nitrogen oxides (NOx).

The operation of the engine 22 is controlled by an electronic controlunit 24 for an engine (hereinafter referred to as an “engine ECU”).Although not illustrated, the engine ECU 24 is constituted as amicroprocessor centered on a CPU, and includes, in addition to the CPU,a ROM that stores a processing program, a RAM that temporarily storesdata, input and output ports, and a communication port. Signals fromvarious sensors required to control the operation of the engine 22 areinput to the engine ECU 24 via the input port. The signals to be inputto the engine ECU 24 may include the followings.

-   -   A crank angle θcr from a crank position sensor 140 that detects        the rotational position of the crankshaft 26    -   A cooling water temperature Tw from a water temperature sensor        142 that detects the temperature of cooling water of the engine        22    -   Cam angles θci, θco from a cam position sensor 144 that detects        the rotational position of an intake cam shaft that opens and        closes the intake valve 128 and the rotational position of an        exhaust cam shaft that opens and closes an exhaust valve    -   A throttle opening degree TH from a throttle valve position        sensor 146 that detects the position of the throttle valve 124    -   The quantity Qa of intake air from an air flow meter 148        attached to an intake pipe    -   An intake temperature Ta from a temperature sensor 149 attached        to the intake pipe    -   An intake air pressure Pin from an intake air pressure sensor        158 that detects pressure within the intake pipe    -   An air-fuel ratio AF from an air-fuel ratio sensor 135 a    -   An oxygen signal O2 from an oxygen sensor 135 b

A knock signal Ks from a knock sensor 159 that is attached to a cylinderblock to detect vibration caused by occurrence of knocking

Various control signals for controlling the operation of the engine 22are output from the engine ECU 24 via the output port. The signals to beoutput from the engine ECU 24 may include the followings.

-   -   A drive control signal to a throttle motor 136 that regulates        the position of the throttle valve 124    -   A drive control signal to a fuel injection valve 126    -   A drive control signal to an ignition coil 138 integrated with        an ignitor

The engine ECU 24 is connected to the HVECU 70 via the communicationport, and controls the operation of the engine 22 depending on a controlsignal from the HVECU 70 and outputs data about the operational state ofthe engine 22 to the HVECU 70 if necessary. The engine ECU 24 calculatesthe rotational speed of the crankshaft 26, that is, the rotational speedNe of the engine 22, on the basis of the crank angle θcr from the crankposition sensor 140. Additionally, the engine ECU 24 calculates thevolume efficiency (the ratio of volume of air actually inhaled in onecycle to stroke volume per one cycle of the engine 22) KL, on the basisof the quantity Qa of intake air from the air flow meter 148 and therotational speed Ne of the engine 22.

As illustrated in FIG. 1, the planetary gear 30 is constituted as asingle pinion type planetary gear mechanism. A rotor of the motor MG1 isconnected to a sun gear of the planetary gear 30. A driving shaft 36coupled to driving wheels 38 a, 38 b via a differential gear 37 isconnected to a ring gear of the planetary gear 30. The crankshaft 26 ofthe engine 22 is connected to a carrier of the planetary gear 30 via adamper 28 serving as a torsion element.

The motor MG1 is constituted as, for example, a synchronous generatormotor, and as described above, the rotor is connected to the sun gear ofthe planetary gear 30. The motor MG2 is constituted as, for example, asynchronous generator motor, and a rotor thereof is connected to thedriving shaft 36. The inverters 41, 42 are connected to a battery 50 viaa power line 54. The motors MG1, MG2 are rotationally driven bycontrolling switching of a plurality of switching elements (notillustrated) of the inverters 41, 42 using an electronic control unit 40for a motor (hereinafter referred to as a “motor ECU”).

Although not illustrated, the motor ECU 40 is constituted as amicroprocessor centered on a CPU, and includes, in addition to the CPU,a ROM that stores a processing program, a RAM that temporarily storesdata, input and output ports, and a communication port. Signals fromvarious sensors required to control the driving of the motors MG1, MG2are input to the motor ECU 40 via the input port. The signals to beinput to the motor ECU 40 may include the followings.

-   -   Rotational positions θm1 and θm2 from rotational position        detecting sensors 43, 44 that detect rotational positions of the        rotors of the motors MG1, MG2    -   Phase currents from current sensors that detect currents that        flow to respective phases of the motors MG1, MG2

Switching control signals or the like to the plurality of switchingelements (not illustrated) of the inverters 41, 42 are output from themotor ECU 40 via the output port. The motor ECU 40 is connected to theHVECU 70 via the communication port, and controls the operation of themotors MG1, MG2 depending on a control signal from the HVECU 70 andoutputs data about the drive state of the motors MG1, MG2 to the HVECU70 if necessary. In addition, the motor ECU 40 calculates the rotationalspeeds Nm1, Nm2 of the motors MG1, MG2, on the basis of the rotationalpositions θm1 and θm2 of the rotors of the motors MG1, MG2 from therotational position detecting sensors 43, 44.

The battery 50 is constituted as, for example, a lithium ion secondarybattery or a nickel hydrogen secondary battery, and as described above,is connected to the inverters 41, 42 via the power line 54. The battery50 is managed by an electronic control unit 52 for a battery(hereinafter referred to as a “battery ECU”).

Although not illustrated, the battery ECU 52 is constituted as amicroprocessor centered on a CPU, and includes, in addition to the CPU,a ROM that stores a processing program, a RAM that temporarily storesdata, input and output ports, and a communication port. Signals fromvarious sensors required to manage the battery 50 are input to thebattery ECU 52 via the input port. The signals to be input to thebattery ECU 52 may include the followings.

-   -   A battery voltage Vb from a voltage sensor 51 a installed        between terminals of the battery 50    -   A battery current Ib from a current sensor 51 b attached to an        output terminal of the battery 50    -   A battery temperature Tb from a temperature sensor 51 c attached        to the battery 50

The battery ECU 52 is connected to the HVECU 70 via the communicationport, and outputs data about the state of the battery 50 to the HVECU 70if necessary. The battery ECU 52 calculates a power storage rate SOC, onthe basis of an integrated value of the battery current Ib from thecurrent sensor 51 b. The power storage rate SOC is a rate of thecapacity of power that is dischargeable from the battery 50 to the totalcapacity of the battery 50. Additionally, the battery ECU 52 calculatesinput and output limits Win, Wout, on the basis of the calculated powerstorage rate SOC, and the battery temperature Tb from the temperaturesensor 51 c. The input and output limits Win, Wout of the battery 50 aremaximum allowable powers that may charge and discharge the battery 50.

Although not illustrated, the HVECU 70 is constituted as amicroprocessor centered on a CPU, and includes, in addition to the CPU,a ROM that stores a processing program, a RAM that temporarily storesdata, input and output ports, and a communication port. Signals fromvarious sensors are input to the HVECU 70 via the input port. Thesignals to be input to the HVECU 70 may include the followings.

-   -   An ignition signal from an ignition switch 80    -   A shift position SP from a shift position sensor 82 that detects        the operative position of a shift lever 81    -   An accelerator opening degree Acc from an accelerator pedal        position sensor 84 that detects the amount of stepping of an        accelerator pedal 83    -   A brake pedal position BP from a brake pedal position sensor 86        that detects the amount of stepping of a brake pedal 85    -   A vehicle speed V from a vehicle speed sensor 88

The HVECU 70 is connected to the engine ECU 24, the motor ECU 40, andthe battery ECU 52 via the communication port, and performs the exchangeof various control signals, and data of the engine ECU 24, the motor ECU40, the battery ECU 52.

In the hybrid vehicle 20 of the example configured in this way, arequired torque Tp* of the driving shaft 36 is set on the basis of theaccelerator opening degree Acc and the vehicle speed V, and the engine22 and the motors MG1, MG2 are controlled so that the required torqueTp* is output to the driving shaft 36 within ranges of the input andoutput limits Win, Wout of the battery 50, with the intermittentoperation of the engine 22.

Next, the operation of the hybrid vehicle 20 of the example configuredin this way, and particularly, the control of the engine 22 will bedescribed. FIG. 3 is a flowchart illustrating an example of a controlroutine to be executed by the HVECU 70 of the example. The main routineis executed when the operation of the engine 22 is started.

If the control routine is executed, first, the starting point watertemperature Twst is input to the HVECU 70 (Step S100). Here, thestarting point water temperature Twst is given by inputting a value,which is detected by the water temperature sensor 142 when the operationof the engine 22 is started (when the execution of the main routine isstarted), through communication from the engine ECU 24.

Subsequently, the starting point water temperature Twst is compared witha threshold value Twref1, and a threshold value Twref2 higher than thethreshold value Twref1 (Step S110). Here, the threshold value Twref1 isa threshold value used to estimate (determine) whether or not apurification catalyst 134 a is in an inactive state (hereinafterreferred to as a “first predetermined state”), and for example, 35° C.,40° C., 45° C., or the like can be used. The threshold value Twref2 is athreshold value used to estimate (determine) whether or not there is astate (hereinafter referred to as a “second predetermined state”) where,since the temperature within the combustion chamber 129 is relativelylow and fuel is apt not to be atomized, combustion is apt to becomeunstable and the discharge amount of particulate matter from the engine22 (discharge particle number (PN)) is apt to increase, and for example,55° C., 60° C., 65° C., or the like can be used.

In Step S110, when the starting point water temperature Twst is higherthan the threshold value Twref2, it is determined that the state of thepurification catalyst 134 a is neither the first predetermined state northe second predetermined state, execution of normal control of theengine 22 is started (Step S160), and the main routine is ended. Here,the operation when the engine 22 is normally controlled will bedescribed. In this case, the HVECU 70 calculates a drive power Pp* ofthe driving shaft 36 by multiplying the required torque Tp* of thedriving shaft 36 by a rotational speed Np (for example, the rotationalspeed Nm2 of the motor MG2, or the like) of the driving shaft 36, andcalculates a required power Pv* of the vehicle by subtracting acharge/discharge required power Pb* (a positive value when beingdischarged from the battery 50) of the battery 50 from the drive powerPp*. Subsequently, the required power Pv* of the vehicle is set to atarget power Pe* of the engine 22, and a target rotational speed Ne* anda target torque Te* of the engine 22 are set on the basis of the targetpower Pe* and an operation line for efficiently operating the engine 22.Next, a torque command Tm1* of the motor MG1 is set so that therotational speed Ne of the engine 22 may become target rotational speedNe*, and a torque command Tm2* of the motor MG2 is set so that therequired torque Tp* is output to the driving shaft 36 within the rangesof the input and output limits Win, Wout of the battery 50. Then, thetarget rotational speed Ne* and the target torque Te* of the engine 22are transmitted to the engine ECU 24, and the torque commands Tm1*, Tm2*of the motors MG1, MG2 are transmitted to the motor ECU 40. The engineECU 24 performs an intake air amount control, a fuel injection control,an ignition control, and the like of the engine 22 so that the engine 22is operated at an operation point based on the target rotational speedNe* and the target torque Te*. The motor ECU 40 performs switchingcontrol of the switching elements of the inverters 41, 42 so that themotors MG1, MG2 are driven by the torque commands Tm1*, Tm2*.

In Step S110, when the starting point water temperature Twst is equal toor lower than the threshold value Twref1, it is determined that thecurrent state is the first predetermined state and the secondpredetermined state, and execution of catalyst warm-up control of theengine 22 is started (Step S120). Here, the catalyst warm-up control ofthe engine 22 is a control in which the engine 22 is controlled so thatthe power Pe of the engine 22 is limited to an upper limit power Pe1 orlower and warm-up (hereinafter referred to as “catalyst warm-up”) of thepurification catalyst 134 a is performed. As the upper limit power Pe1,for example, 0.8 kW, 1.0 kW, 1.2 kW, or the like can be used. In thiscase, the HVECU 70 limits the required power Pv* of the above-describedvehicle to the upper limit power Pe1 (upper limit guard) to set thetarget power Pe* of the engine 22, and similar to the normal control,sets the target rotational speed Ne* and the target torque Te* of theengine 22 and the torque commands Tm1*, Tm2* of the motors MG1, MG2 totransmit these settings to the engine ECU 24 and the motor ECU 40. Theengine ECU 24 controls the ignition timing of the engine 22 as to belater than an ignition timing for efficiently operating the engine 22and to be suitable for the catalyst warm-up, in the ignition control.Additionally, in the intake air amount control and the fuel injectioncontrol, a throttle opening degree and a fuel injection amount areregulated so that the engine 22 is operated at an operation point basedon the target rotational speed Ne* and the target torque Te*, using theignition timing as an ignition timing suitable for the catalyst warm-up.The catalyst warm-up can be promoted by controlling the ignition timingas to be suitable for the catalyst warm-up in this way.

Next, the cooling water temperature Tw of the engine 22 and an operationtime top of the engine 22 are input (Step S130). Here, the cooling watertemperature Tw is given by inputting a value detected by the watertemperature sensor 142 through communication from the engine ECU 24.Additionally, the operation time top of the engine 22 is given byinputting a value clocked by a timer (not illustrated) as the time fromthe start of the operation of the engine 22.

Subsequently, the cooling water temperature Tw of the engine 22 iscompared with the threshold value Twref1 (Step S132), the operation timetop of the engine 22 is compared with a threshold value topref1, and areturn to Step S130 is performed when the cooling water temperature Twof the engine 22 is equal to or lower than the threshold value Twref1and the operation time top of the engine 22 is lower than the thresholdvalue topref1 (Step S134). Then, while processing of Steps S130 to S134is executed, when the cooling water temperature Tw of the engine 22becomes higher than the threshold value Twref1 in Step S132 or when theoperation time top of the engine 22 becomes equal to or higher than thethreshold value topref1 in Step S134, the execution of the catalystwarm-up control of the engine 22 is executed, the execution of thenormal control of the engine 22 is started (Step S160), and the mainroutine is ended. Here, the threshold value Twref1 and the thresholdvalue topref1 are threshold values used to determine whether or not theexecution of the catalyst warm-up control may be ended (whether a shiftto the normal control may be performed). As the threshold value topref,for example, 65 sec, 70 sec, 75 sec, or the like can be used.

In this way, by shifting the control of the engine 22 from the catalystwarm-up control to the normal control when the cooling water temperatureTw of the engine 22 becomes higher than the threshold value Twref1 orthe operation time top of the engine 22 becomes equal to or higher thanthe threshold value topref1, the execution time of the catalyst warm-upcontrol can be prevented from becoming relatively long when a rise inthe cooling water temperature Tw becomes relatively gentle, as comparedto a case where the control of the engine 22 is shifted from thecatalyst warm-up control to the normal control when the cooling watertemperature Tw becomes higher than the threshold value Twref1.Accordingly, the time during which the output from the motor MG2 andeventually the discharge power from the battery 50 is apt to becomegreat can be prevented from continuing relatively long, and the powerstorage proportion SOC of the battery 50 can be prevented from decliningrelatively greatly.

In Step S110, when the starting point water temperature Twst is higherthan the threshold value Twref1 and equal to or lower than the thresholdvalue Twref2, it is determined that the current state is not the firstpredetermined state but the second predetermined state, and theexecution of the PN suppression control of the engine 22 is started(Step S140). Here, the PN suppression control of the engine 22 is acontrol in which the engine 22 is controlled so that the power Pe of theengine 22 is limited to the upper limit power Pe2 or lower and thedischarge amount of particulate matter from the engine 22 is suppressed.The upper limit power Pe2 is greater than the upper limit power Pe1. Asthe upper limit power Pe2, for example, 4.5 kW, 5.0 kW, 5.5 kW, or thelike can be used. In this case, the HVECU 70 limits (upper limit guard)the required power Pv* of the above-described vehicle to the upper limitpower Pe2 to set the target power Pe* of the engine 22, and similar tothe normal control, sets the target rotational speed Ne* and the targettorque Te* of the engine 22 and the torque commands Tm1*, Tm2* of themotors MG1, MG2 to transmit these settings to the engine ECU 24 and themotor ECU 40. By limiting the power Pe from the engine 22 to the upperlimit power Pe2 or lower in this way, the discharge amount ofparticulate matter from the engine 22 can be suppressed as compared to acase where the Power Pe is not limited to the upper limit power Pe2 orlower.

Next, the cooling water temperature Tw of the engine 22 and theoperation time top of the engine 22 are input (Step S150), the coolingwater temperature Tw of the engine 22 is compared with the thresholdvalue Twref2 (Step S152), the operation time top of the engine 22 iscompared with the threshold value topref2 (Step S154), and a return toStep S150 is performed when the cooling water temperature Tw of theengine 22 is equal to or lower than the threshold value Twref2 and theoperation time top of the engine 22 is lower than the threshold valuetopref2. Then, while processing of Steps S150 to S154 is executed, whenthe cooling water temperature Tw of the engine 22 becomes higher thanthe threshold value Twref2 in Step S152 or when the operation time topof the engine 22 becomes equal to or higher than the threshold valuetopref2 in Step S154, the execution of the PN suppression control of theengine 22 is executed, the execution of the normal control of the engine22 is started (Step S160), and the main routine is ended. Here, thethreshold value Twref2 and the threshold value topref2 are thresholdvalues used to determine whether or not the execution of the PNsuppression control may be ended (whether a shift to the normal controlmay be performed). As the threshold value topref, for example, 3 sec, 4sec, 5 sec, or the like can be used.

In this way, by shifting the control of the engine 22 from the PNsuppression control to the normal control when the cooling watertemperature Tw of the engine 22 becomes higher than the threshold valueTwref2 or the operation time top of the engine 22 becomes equal to orhigher than the threshold value topref2, the execution time of the PNsuppression control can be prevented from becoming relatively long whena rise in the cooling water temperature Tw becomes relatively gentle, ascompared to a case where the control of the engine 22 is shifted fromthe PN suppression control to the normal control when the cooling watertemperature Tw becomes higher than the threshold value Twref2.Accordingly, the time during which the output from the motor MG2 andeventually the discharge power from the battery 50 is apt to becomegreat can be prevented from continuing relatively long, and the powerstorage proportion SOC of the battery 50 can be prevented from decliningrelatively greatly.

In addition, in the example, during the execution of the catalystwarm-up control, when the cooling water temperature Tw of the engine 22becomes higher than the threshold value Twref1 or when the operationtime top of the engine 22 becomes equal to or higher than the thresholdvalue topref1, the control of the engine 22 is not shifted from thecatalyst warm-up control to the PN suppression control but is shiftedfrom the catalyst warm-up control to the normal control even if thecooling water temperature Tw is equal to or lower than the thresholdvalue Twref2. It is believed that this is because the temperature withinthe cylinder of the engine 22 becomes high to a certain degree even ifthe cooling water temperature Tw is equal to or lower than the thresholdvalue Twref2 when the operation of the engine 22 is performed for acertain amount of time.

In the hybrid vehicle 20 of the example described above, when thestarting point water temperature Twst is higher than the threshold valueTwref2 and higher than the threshold value Twref1, the required powerPv* of the vehicle is set to the target power Pe* of the engine 22, andthe normal control of the engine 22 is executed. When the starting pointwater temperature Twst is equal to or lower than the threshold valueTwref1, the required power Pv* of the vehicle is limited (upper limitguard) to the upper limit power Pe1, the target power Pe* is set, andthe catalyst warm-up control of the engine 22 is executed. When thecooling water temperature Tw of the engine 22 becomes higher than thethreshold value Twref1 or the operation time top of the engine 22becomes equal to or higher than the threshold value topref1, the controlof the engine 22 is shifted from the catalyst warm-up control to thenormal control. When the starting point water temperature Twst is higherthan the threshold value Twref1 and is equal to or lower than thethreshold value Twref2, the required power Pv* of the vehicle is limited(upper limit guard) to the upper limit power Pe2 that is greater thanupper limit power Pe1, the target power Pe* is set, and the PNsuppression control of the engine 22 is executed. When the cooling watertemperature Tw of the engine 22 becomes higher than the threshold valueTwref2 and the operation time top of the engine 22 becomes equal to orhigher than the threshold value topref2, the control of the engine 22 isshifted from the PN suppression control to the normal control.Accordingly, when a rise in the cooling water temperature Tw of theengine 22 is relatively gentle, the execution time of the catalystwarm-up control and the PN suppression control can be prevented frombecoming relatively long. As a result, the time during which the outputfrom the motor MG2 and eventually the discharge power from the battery50 is apt to become great can be prevented from continuing relativelylong, and the power storage proportion SOC of the battery 50 can beprevented from declining relatively greatly.

In the hybrid vehicle 20 of the example, a fixed value is used as theupper limit power Pe2. However, the upper limit power Pe2 may be setaccording to the starting point water temperature Twst. In this case,the upper limit power Pe2 can be set, for example, by determining therelationship between the starting point water temperature Twst and theupper limit power Pe2 and storing the relationship in advance as a mapin a ROM (not illustrated), and by deriving a corresponding upper limitpower Pe2 if the starting point water temperature Twst is given. Anexample of the map in which the relationship between the starting pointwater temperature Twst and the upper limit power Pe2 is determined isillustrated in FIG. 4. In the example of FIG. 4, the upper limit powerPe2 is set so that the upper limit power when the starting point watertemperature Twst is low becomes smaller than that when the startingpoint water temperature is high, specifically, becomes smaller as thestarting point water temperature Twst becomes lower. For example, whenthe starting point water temperature Twst is near the threshold valueTwref1, 4.5 kW, 5.0 kW, 5.5 kW, or the like is set to the upper limitpower Pe2, and when the starting point water temperature Twst is nearthe threshold value Twref2, 7.5 kW, 8.0 kW, 8.5 kW, or the like is setto the upper limit power Pe2. When the starting point water temperatureTwst is low, it is believed that, as compared to that when the startingpoint water temperature Twst is high, the temperature within thecylinder of the engine 22 is low and the discharge amount of particulatematter from the engine 22 is apt to increase. Therefore, the dischargeamount of particulate matter from the engine 22 can be moreappropriately suppressed by setting the upper limit power Pe2 so thatthe upper limit power when the starting point water temperature Twst islow becomes smaller than that when the starting point water temperatureis high.

In the hybrid vehicle 20 of the example, a fixed value is used as thethreshold value topref2. However, the threshold value topref2 may be setaccording to the starting point water temperature Twst. In this case,the threshold value topref2 may be set, for example, by determining therelationship between the starting point water temperature Twst and thethreshold value topref2 and storing the relationship in advance as a mapin a ROM (not illustrated), and by deriving a corresponding thresholdvalue topref2 from this map if the starting point water temperature Twstis given. An example of the map in which the relationship between thestarting point water temperature Twst and the threshold value topref2 isdetermined is illustrated in FIG. 5. In the example of FIG. 5, thethreshold value topref2 is set so that the threshold value when thestarting point water temperature Twst is low becomes greater than thatwhen the starting point water temperature is high, specifically, becomesgreater as the starting point water temperature Twst becomes lower. Forexample, when the starting point water temperature Twst is near thethreshold value Twref1, 3 sec, 4 sec, 5 sec, or the like is set to thethreshold value topref2, and when the starting point water temperatureTwst is near the threshold value Twref2, 1 sec, 1.5 sec, 2 sec, is setto the threshold value topref2. As described above, when the startingpoint water temperature Twst is low, it is believed that, as compared tothat when the starting point water temperature Twst is high, thetemperature within the cylinder of the engine 22 is low and thedischarge amount of particulate matter from the engine 22 is apt toincrease. Therefore, the execution time (time for suppressingparticulate matter from the engine 22) of the PN suppression control canbe made more suitable by setting the threshold value topref2 so that sothat the threshold value topref2 when the starting point watertemperature Twst is low becomes longer than that when the starting pointwater temperature Twst is high.

In the hybrid vehicle 20 of the example, the control routine of FIG. 3is executed. However, a control routine of FIG. 6 may be executed. Here,the routine of FIG. 6 is the same as that of the routine of FIG. 3except that the processing of Step S200 is executed instead of theprocessing of Step S100 with respect to the routine of FIG. 3 and theprocessing of Step S210 is added. Therefore, the same processing will bedesignated by the same step numbers, and the detailed descriptionthereof will be omitted.

In the control routine of FIG. 6, the HVECU 70 inputs a stop time toffof the engine 22 in addition to the starting point water temperatureTwst (Step S200). Here, the stop time toff is given by inputting a valueclocked by a timer (not illustrate) as a time from the end of a previousoperation of the engine 22 to the start of a current operation.

Then, in Step S110, when the starting point water temperature Twst ishigher than the threshold value Twref1 and is equal to or lower than thethreshold value Twref2, the stop time toff of the engine 22 is comparedwith the threshold value toffref (Step S210). Here, the threshold valuetoffref is a threshold value used to determine whether or not thetemperature within the cylinder has dropped to a certain degree duringthe operation stop of the engine 22, for example, 25 sec, 30 sec, 35sec, or the like can be used. The processing of this Step S210 is basedon a reason it is believed that the temperature within the cylinder ofthe engine 22 is still relatively high and the discharge amount ofparticulate matter from the engine 22 does not increase so much when thestop time toff is relatively short.

In Step S210, when the stop time toff of the engine 22 is equal to orgreater than the threshold value toffref, it is determined that thetemperature within the cylinder has drooped to a certain degree duringthe operation stop of the engine 22, and the execution of the PNsuppression control of the engine 22 is started (Step S140). Thereafter,the control of the engine 22 is shifted from the PN suppression controlto the normal control (Steps S150 to S160), and the main routine isended. In this case, the discharge amount of particulate matter from theengine 22 can be prevented from increasing by executing the PNsuppression control.

In Step S210, when the stop time toff of the engine 22 is smaller thanthe threshold value toffref, it is determined that the temperaturewithin the cylinder does not drop so much during the operation stop ofthe engine 22, the execution of the normal control is started withoutexecuting the PN suppression control of the engine 22 (Step S160), andthe main routine is ended. In this case, by starting the execution ofthe normal control without executing the PN suppression control of theengine 22, the power Pe from the engine 22 can be increased, and theoutput from the motor MG2 and eventually the discharge power from thebattery 50 can be further prevented from becoming relatively great.

FIG. 7 is an explanatory view illustrating an example of an aspect ofthe state and control of the engine 22, in the case of a modificationexample. In addition, in FIG. 7, the time when the cooling watertemperature Tw is varying within a range that is higher than thethreshold value Twref1 and is equal to or lower than the threshold valueTwref2 is considered. As illustrated in the drawing, when the stop timetoff is equal to or lower than the threshold value toffref at the startof the operation of the engine 22, a shift to the normal control isperformed after the PN suppression control is executed, and when thestop time toff is smaller than the threshold value toffref, the normalcontrol is executed without executing the PN suppression control.Accordingly, when the stop time toff is greater than the threshold valuetoffref, the discharge amount of particulate matter from the engine 22can be prevented from increasing. When the stop time toff is smallerthan the threshold value toffref, the output from the motor MG2 andeventually the discharge power from the battery 50 can be furtherprevented from becoming relatively great.

In this modification example, a fixed value is used as the thresholdvalue toffref. However, the threshold value toffref may be set accordingto the starting point water temperature Twst. In this case, thethreshold value toffref may be set, for example, by determining therelationship between the starting point water temperature Twst and thethreshold value toffref and storing the relationship in advance as a mapin a ROM (not illustrated), and by deriving a corresponding thresholdvalue toffref from this map if the starting point water temperature Twstis given. An example of the map in which the relationship between thestarting point water temperature Twst and the threshold value toffref isdetermined is illustrated in FIG. 8. In the example of FIG. 8, thethreshold value toffref is set so that the upper limit power when thestarting point water temperature Twst is low becomes smaller than thatwhen the starting point water temperature is high, specifically, becomessmaller as the starting point water temperature Twst becomes lower. Forexample, when the starting point water temperature Twst is near thethreshold value Twref1, 25 sec, 30 sec, 35 sec, or the like is set tothe threshold value toffref, and when the starting point watertemperature Twst is near the threshold value Twref2, 55 sec, 60 sec, 65sec, is set to the threshold value toffref. When the starting pointwater temperature Twst is low, it is believed that, as compared to thatwhen the starting point water temperature Twst is high, the temperaturewithin the cylinder of the engine 22 is apt to be low. Therefore,whether or not the PN suppression control is executed can be moreappropriately determined by setting the threshold value toffref so thatthe threshold value when the starting point water temperature Twst islow becomes smaller than that when the starting point water temperatureis high.

In the hybrid vehicle 20 of the example, the control routine of FIG. 3is executed. However, a control routine of FIG. 9 may be executed. Here,the routine of FIG. 9 is the same as that of the routine of FIG. 3except that the processing of Step S300 is executed instead of theprocessing of Step S150 with respect to the routine of FIG. 3 and theprocessing of Step S310 is added. Therefore, the same processing will bedesignated by the same step numbers, and the detailed descriptionthereof will be omitted.

In the control routine of FIG. 9, the HVECU 70 inputs an integrated airquantity Ga of the engine 22 (Step S300), in addition to the coolingwater temperature Tw of the engine 22 and the operation time top of theengine 22, similar to Step S150 of FIG. 2, if the execution of the PNsuppression control is started (Step S140). Here, the integrated airquantity Ga of the engine 22 is given by inputting a value, which iscalculated as an integrated value from the start of the operation of theengine 22 of the quantity Qa of intake air from the air flow meter 148,through communication from the engine ECU 24.

Subsequently, the cooling water temperature Tw of the engine 22 iscompared with the threshold value Twref2 (Step S152), the operation timetop of the engine 22 is compared with the threshold value topref2 (StepS154), the integrated air quantity Ga of the engine 22 is compared withthe threshold value Garef (Step S310), and a return to Step S150 isperformed when the cooling water temperature Tw of the engine 22 isequal to or lower than the threshold value Twref2 and the operation timetop of the engine 22 is smaller than the threshold value topref2 andwhen the integrated air quantity Ga is smaller than the threshold valueGaref. Then, while the processing of Steps S150 to S310 is executed,when the cooling water temperature Tw of the engine 22 becomes equal toor higher than the threshold value topref2 in Step S152, when theoperation time top of the engine 22 becomes higher than the thresholdvalue Twref2 in Step S154, or when the integrated air quantity Ga of theengine 22 becomes greater than the threshold value Garef in Step S310,the execution of the PN suppression control of the engine 22 is ended,the execution of the normal control is started (Step S160), and the mainroutine is ended. Here, the threshold value Garef is a threshold valueused to determine whether or not the execution of the PN suppressioncontrol may be ended (whether a shift to the normal control may beperformed). As the threshold value Garef, for example, 15 g, 17 g, 20 g,or the like can be used.

In this way, when the cooling water temperature Tw of the engine 22becomes higher than the threshold value Twref2, when the operation timetop of the engine 22 becomes equal to or higher than the threshold valuetopref2, or when the integrated air quantity Ga of the engine 22 becomesgreater than the threshold value Garef, that is, when the conditions ofthe integrated air quantity Ga are satisfied even if the condition ofthe cooling water temperature Tw and the condition of the operation timetop are not satisfied, the execution time of the PN suppression controlcan be further prevented from becoming relatively long by shifting thecontrol of the engine 22 from the PN suppression control to the normalcontrol.

In this modification example, a fixed value is used as the thresholdvalue Garef. However, the threshold value Garef may be set according tothe starting point water temperature Twst. In this case, the thresholdvalue Garef is set, for example, by determining the relationship betweenthe starting point water temperature Twst and the threshold value Garefand storing the relationship in advance as a map in a ROM (notillustrated), and by deriving a corresponding threshold value Garef fromthis map if the starting point water temperature Twst is given. Anexample of the map in which the relationship between the starting pointwater temperature Twst and the threshold value Garef is determined isillustrated in FIG. 10. In the example of FIG. 10, the threshold valueGaref is set so as to become greater when the starting point watertemperature Twst is low than when the starting point water temperatureis high, specifically, becomes greater as the starting point watertemperature Twst becomes lower. For example, when the starting pointwater temperature Twst is near the threshold value Twref1, 15 g, 17 g,20 g, or the like is set to the threshold value Garef; and when thestarting point water temperature Twst is near the threshold valueTwref2, 8 g, 10 g, 12 g, is set to the threshold value Garef. Asdescribed above, when the starting point water temperature Twst is low,it is believed that, as compared to that when the starting point watertemperature Twst is high, the temperature within the cylinder of theengine 22 is low and the discharge amount of particulate matter from theengine 22 is apt to increase. Therefore, the execution time (time forsuppressing particulate matter from the engine 22) of the PN suppressioncontrol can be made more suitable by setting the threshold value Garefso as to become greater when the starting point water temperature Twstis low than that when the starting point water temperature Twst is high.

In the hybrid vehicle 20 of the example, when the PN suppression controlis executed, the required power Pv* of the vehicle is limited to theupper limit power Pe2 and the target power Pe* of the engine 22 is set.However, as illustrated in FIG. 11, when the required power Pv* of thevehicle becomes greater than a sum (Wout+Pe2) of the load limit Wout ofthe battery 50 and the upper limit power Pe2, the target power Pe* ofthe engine 22 may be made greater than the upper limit power Pe2. Ifthis is the case, it is possible to further cope with the acceleratoroperation of a driver.

In the hybrid vehicle 20 of the example, when the catalyst warm-upcontrol is executed, the required power Pv* of the vehicle is limited tothe upper limit power Pe1 and the target power Pe* of the engine 22 isset, and when the PN suppression control is executed, the required powerPv* of the vehicle is limited to the upper limit power Pe2 and thetarget power Pe* of the engine 22 is set. However, when the catalystwarm-up control is executed, the upper limit power Pe1 may be set to thetarget power Pe* irrespective of the required power Pv*, and when the PNsuppression control is executed, the upper limit power Pe2 may be set tothe target power Pe* irrespective of the required power Pv*.

In the hybrid vehicle 20 of the example, during the execution of thecatalyst warm-up control, when the cooling water temperature TW of theengine 22 becomes higher than the threshold value Twref1 or when theoperation time top of the engine 22 becomes equal to or higher than thethreshold value topref1, the control of the engine 22 is shifted fromthe catalyst warm-up control to the normal control. However, during theexecution of the catalyst warm-up control, when the cooling watertemperature Tw becomes higher than the threshold value Twref1 in arelatively short time (for example, the operation time top is a timethat is shorter than the above-described threshold value topref2), thecontrol of the engine 22 may be shifted to the normal control afterbeing transferred from the catalyst warm-up control to the PNsuppression control. The execution time of the PN suppression control inthis case can be, for example, a time obtained by subtracting theexecution time of the catalyst warm-up control from the threshold valuetopref2.

In the hybrid vehicle 20 of the example, the power from the motor MG2 isoutput to the driving shaft 36 connected to the driving wheels 38 a, 38b. However, as illustrated in a hybrid vehicle 120 of a modificationexample of FIG. 12, the power from the motor MG2 may be output to avehicle axle (a vehicle axle connected to wheels 39 a, 39 b in FIG. 12)that is different from a vehicle axle (a vehicle axle connected to thedriving wheels 38 a, 38 b) to which the driving shaft 36 is connected.Even in the case of this hardware configuration, the same effects as theexample can be exhibited by executing the control routine of FIG. 3, orthe like, similar to the example.

In the hybrid vehicle 20 of the example, the power from the engine 22 isoutput to the driving shaft 36 connected to the driving wheels 38 a, 38b via the planetary gear 30, and the power from the motor MG2 is outputto the driving shaft 36. However, as illustrated in a hybrid vehicle 220of a modification example of FIG. 13, a configuration in which a motorMG is connected to the driving shaft 36 connected to the driving wheels38 a, 38 b via a transmission 230 and the engine 22 is connected to arotating shaft of the motor MG via a clutch 229 may be adopted, and thepower from the engine 22 may be output to the driving shaft 36 via therotating shaft of the motor MG, and the transmission 230, and the powerfrom the motor MG may be connected to the driving shaft via thetransmission 230. Even in the case of this hardware configuration, thesame effects as the example can be exhibited by executing the controlroutine of FIG. 3, or the like, similar to the example.

Correspondence relationships between the main elements of the exampleand the main elements of the disclosure described in the column of themeans for solving the problems will be described. In the example, theengine 22 may be regarded as an “engine”, the motor MG2 may be regardedas a “motor”, the battery 50 is equivalent to a “battery”, and the HVECU70, the engine ECU 24, and the motor ECU 40 may be regarded as “acontroller”.

In addition, since the correspondence relationships between the mainelements of the example and the main elements of the disclosuredescribed in the column of means for solving the problems are examplesfor specifically describing modes for carrying out the disclosuredescribed in the column of the means for the example to solve theproblems, the disclosure is not limited to the elements of thedisclosure described in the column of the means for solving theproblems. That is, interpretation about the disclosure described in thecolumn of the means for solving the problems should be performed on thebasis of the description of the column, and the example are merelyspecific examples of the disclosure described in the column of the meansfor solving the problems.

Although the modes for carrying out the disclosure have been describedabove using the example, the disclosure is not limited to such exampleat all, and can be naturally carried out in various forms withoutdeparting from the scope of the disclosure.

The disclosure is available for a hybrid vehicle manufacturing industry,and the like.

What is claimed is:
 1. A hybrid vehicle by comprising: an engine and amotor for driving; a battery that exchanges power with the motor; acontroller configured to control the engine and the motor so that theengine is driven depending on a required output for driving while beingintermittently operated, wherein the control controller, executes normalcontrol in which the engine is controlled so that a target output of theengine according to the required output is output from the engine when astarting point water temperature that is a cooling water temperature atthe start of the operation of the engine is higher than a secondpredetermined temperature higher than a first predetermined temperature,executes first control in which the engine is controlled so that anoutput of the engine is limited to a first predetermined output or lowerand a catalyst of an exhaust gas control apparatus of the engine iswarmed up when the starting point water temperature is equal to or lowerthan the first predetermined temperature, and then shifts to the normalcontrol when the cooling water temperature becomes higher than the firstpredetermined temperature or when a first predetermined time has lapsedfrom the start of the operation of the engine, and executes secondcontrol in which the engine is controlled so that the output of theengine is limited to a second predetermined output or lower that isgreater than the first predetermined output and a discharge amount ofparticulate matter from the engine is suppressed when the starting pointwater temperature is higher than the first predetermined temperature andis equal to or lower than the second predetermined temperature, and thenshifts to the normal control when the cooling water temperature becomeshigher than the second predetermined temperature or when a secondpredetermined time has lapsed from the start of the operation of theengine.
 2. The hybrid vehicle according to claim 1, wherein the secondpredetermined output is set so that the second predetermined output whenthe starting point water temperature is low becomes smaller than thatwhen the starting point water temperature is high.
 3. The hybrid vehicleaccording to claim 1, wherein the second predetermined time is set sothat the second predetermined time when the starting point watertemperature is low becomes longer than that when the starting pointwater temperature is high.
 4. The hybrid vehicle according to claim 1,wherein when the starting point water temperature is higher than thefirst predetermined temperature and is equal to or lower than the secondpredetermined temperature, the controller is configured to shift to thenormal control after the second control is executed when a stop timefrom the end of a previous operation of the engine to the start of acurrent operation of the engine is equal to or greater than a thirdpredetermined time, and executes the normal control without executingthe second control when the stop time is smaller than the thirdpredetermined time.
 5. The hybrid vehicle according to claim 4, whereinthe third predetermined time is set so that the third predetermined timewhen the starting point water temperature is low becomes shorter thanthat when the starting point water temperature is high.
 6. The hybridvehicle according to claim 1, wherein the controller is configured toshift to the normal control when an integrated air quantity from thestart of the operation of the engine reaches a predetermined airquantity or greater even when the cooling water temperature ismaintained lower than the second predetermined temperature and a timeform the start of the operation of the engine is within the secondpredetermined time, during the execution of the second control.
 7. Thehybrid vehicle according to claim 6, wherein the predetermined airquantity is set so that the predetermined air quantity when the startingpoint water temperature is low becomes greater than that when thestarting point water temperature is high.